1. Field of the Invention
The present invention relates to a refrigerant composition which includes lubricants for use in a refrigeration system.
2. Description of Related Art
Refrigerant fluids generally have powerful degreasing properties. Therefore, adequately lubricating the piston and cylinder walls and the bearings of the compressor used in cooling systems has heretofore presented a problem. In addition, there is the problem of adequately lubricating the moving parts of valves used in the cooling system. In past practice, an excess of lubricating oil was provided within the cooling system to provide some lubrication of the moving parts.
Examples of the application of PTFE particles can be seen among the references cited below. The McCoy et al. patent shows the use of PTFE particles in a lubricant composition intended primarily as an engine lubricant. The Holzknecht patent relates to a leak sealer for refrigeration systems. The leak sealer of Holzknecht relies on the agglomeration of PTFE particles to plug leaks, and therefore the particle sizes in the composition of Holzknecht are quite large.
None of the references cited below provide for a refrigerant composition which allows for the enhanced lubrication of parts within a cooling system. Therefore, the need persists in the art for a refrigerant composition which provides for enhanced lubrication of the parts of a cooling system.
U.S. Pat. No. 5,792,728, issued to Lin-Sen Yuan et al. on Aug. 11, 1998, is directed to a cutting fluid composition for use in machining operations. The cutting fluid composition includes molybdenum disulfide powder, soap flakes, a liquid PTFE suspension, and water. The liquid PTFE suspension used by Yuan et al. is composed of PTFE, water, and a surfactant. Yuan et al. do not disclose the range of PTFE particle sizes used in their composition.
U.S. Pat. No. 5,744,539, issued to Frederic C. McCoy et al. on Apr. 28, 1998, is directed to lubricant compositions having PTFE (a.k.a. TEFLON(copyright)) particles with an average size ranging from 4 to 6 microns dispersed therein. The compositions of McCoy et al. also include dispersing agents which help keep the TEFLON(copyright) particles from separating from the lubricating oil.
U.S. Pat. No. 5,650,563, issued to B. William Cooper et al. on Jul. 22, 1997, and U.S. Pat. No. 5,440,919, issued to B. William Cooper on Aug. 15, 1995, are directed to methods of introducing a leak detection dye into a refrigeration apparatus. The methods involve the placement of an inert dye impregnated carrier or the placement of a solid pellet of a dye in the desiccant bag of a dehydrator used in the refrigeration apparatus.
U.S. Pat. No. 5,378,123, issued to Carmelo J. Scuderi et al. on Jan. 3, 1995, is directed to an apparatus for recovering refrigerant from a refrigeration system. The apparatus includes a liquid trap which separates the gaseous refrigerant from the liquid refrigerant. The liquid refrigerant from the liquid trap goes to a liquid receiver, while the gaseous refrigerant is directed to a condenser where it is liquified and then directed to the same liquid receiver.
U.S. Pat. No. 4,487,707, issued to Robert H. Holzknecht on Dec. 11, 1984, is directed to a leak sealing composition for refrigeration systems. The composition of Holzknecht includes graphite or TEFLON(copyright) particles, ranging in size from 20 microns to 65 mesh, suspended in refrigeration oil.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
The present invention is directed to a refrigerant composition which includes lubricants. The refrigerant composition of the present invention includes formulations for use in both automotive and residential or building air conditioning units. The refrigerant composition of the present invention includes 25% to 35% by weight of a refrigerant, 60% to 70% by weight of a lubricating oil, and 0.5% to 10% by weight of polytetrafluoroethylene particles. The polytetrafluoroethylene particles used in the present invention range in size from 0.2 xcexcm to 8.0 xcexcm.
Accordingly, it is a principal object of the invention to provide a refrigerant composition which allows the adequate lubrication of moving parts within a cooling system.
It is another object of the invention to provide a refrigerant composition which includes solid lubricating particles which will not be dissolved by the refrigerant component of the composition.
It is a further object of the invention to provide a refrigerant composition which includes PTFE particles.
Still another object of the invention is to provide a refrigerant composition which includes PTFE particles that are small enough to penetrate the interstices between the parts of a cooling system.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification.